Masonry block arrangements; wall units; and, methods

ABSTRACT

Concrete block arrangements are described. The block arrangements are adapted to be interfit, without modification, with at least one, and typically two, additional adjacent concrete blocks in a wall course, with mortarless head joints between the concrete block and the additional concrete block(s). Both stretcher block and corner block versions of the concrete block are described. Also described are: methods of use and assembly; and, resulting wall units.

FIELD OF THE INVENTION

The present disclosure relates to concrete masonry block, and its use in forming wall structures, sometimes referenced as concrete masonry walls. The disclosure particularly concerns: block arrangements provided with advantageous features for engagement with adjacent blocks along a layer or course in a wall to facilitate wall construction; and, various wall constructions made using the blocks. Methods for assembly and use are also characterized.

BACKGROUND

Concrete or masonry wall blocks are well known. In certain applications the blocks are used to form foundation walls, with mortar applied in both bed joints and head joints. Separately positioning mortar in heads joints, in steps separate from bed joint mortar application, is a time consuming task and improvements are sought.

SUMMARY

The present disclosure relates to improvements in which concrete (masonry) block arrangements (or blocks), useable to form walls such as foundation walls, are configured for use with avoidance of mortar in selected head joints at locations where intact blocks engage (interfit with) one another in a concrete masonry unit or wall. In addition to example blocks in accord with this description, also disclosed are wall arrangements and methods and techniques for forming the blocks and the wall arrangements.

Two specific example block arrangements are described in detail, with possible variations characterized. Each specific example generally comprises a concrete block adapted to be interfit, without modification, with at least one and typically two additional concrete blocks in a wall course in a wall section, with mortarless head joints between the concrete block and the at least one additional concrete block. In each instance, the concrete block generally comprises a concrete block body having: first and second opposite bearing surfaces; first and second opposite faces (or sides); and, first and second opposite ends. The first and second opposite bearing surfaces generally correspond to the upper and lower surfaces of the block when the block is oriented for typical use in a wall. The first and second opposite faces (or sides) generally correspond to inner and outer (or opposite) walls or faces in a wall course formed with the block. The first and second opposite ends define regions that are organized vertically in a wall course and typically face toward and away from at least one adjacent block in a corresponding wall course.

A first end of each of two specifically shown example blocks typically comprises a first member of the first projection/receiver arrangement. In these specific examples described, the first end comprises a first receiver member comprising a central recessed (block) section positioned between first and second opposite side sections, projections or ears, defining a u-shaped recess at the first end of the block body, although alternatives are possible. An example preferred u-shaped recess is provided, for convenient interfit with an adjacent block to form a mortarless head joint therebetween.

Alternatives are specifically described for a second end of the concrete block opposite the first end. In one example, the block is a stretcher block, having at the second end a second member of the projection/receiver arrangement, in the form of a projection member. Such stretcher blocks can be inner fit with one another, in a wall course.

In an alternative specific example, the block is a corner block, and the second end includes (as a member of a projection/receiver arrangement) a receiver member second recess adjacent to, and spaced from, the second end and directed toward one of the side walls or faces of the block, to form a corner. In this instance, the receiver or receiver member in the second end also has a u-shaped section, and is configured to interfit with a projection member on an adjacent block, for example a stretcher block as previously characterized, to form a corner in a block course of a wall section.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary, schematic, perspective view of a section of a concrete masonry wall unit constructed utilizing a stretcher block according to the present disclosure.

FIG. 2 is a schematic, perspective, view depicting a stretcher or side block useable in the wall section of FIG. 1.

FIG. 3 is a schematic, fragmentary, top plan view of a head joint in a wall section according to FIG. 1; FIG. 3 showing adjacent stretcher blocks according to FIG. 2 positioned adjacent one another in a course.

FIG. 3A is an enlarged fragmentary view of a portion of FIG. 3.

FIG. 4 is a schematic, perspective view of a fill top block, useable in the masonry wall unit of FIG. 1.

FIG. 4A is a schematic, side elevational view of a fill top block according to FIG. 4, with phantom lines defining internal void or core area.

FIG. 5 is a schematic, perspective, view of a corner block useable to form corners in a wall unit constructed with block according to FIG. 2.

FIG. 6 is a fragmentary, schematic, top plan view of a portion of a block course using blocks according to FIGS. 2 and 5.

FIG. 7 is a schematic, perspective, view of a single ledge block useable in alternate wall units to those depicted in FIG. 1.

FIG. 8 is a schematic, perspective, view of a double ledge block useable in still further alternate wall units to those depicted in FIG. 1.

FIG. 9 is a fragmentary, schematic, depiction of a portion of a section of a first alternate masonry wall unit to the arrangement of FIG. 1, depicted using the ledge block of FIG. 8, the block of FIG. 2, partition block and facing brick.

FIG. 10 is a fragmentary, schematic, perspective view of a portion of a second alternate wall unit to that depicted in FIGS. 1 and 9, using the ledge block of FIG. 7, the block of FIG. 2, partition block and facing brick.

FIG. 11 is a fragmentary, schematic, perspective view of a portion of a double floor slab wall unit, i.e., a third alternate wall unit to that depicted in FIGS. 1, 9 and 10, using, among other things, the blocks of FIGS. 7 and 2, and partition block.

FIG. 12 is a fragmentary, schematic, perspective view of a portion of a fourth alternate concrete masonry wall unit to that depicted in FIGS. 1 and 9-11; using, among other things, the blocks of FIGS. 2 and 8, and partition block.

FIG. 13 is a fragmentary, schematic, perspective view of a portion of a fifth alternate concrete masonry wall unit to the alternatives depicted in FIGS. 1 and 9-12.

FIG. 14 is a fragmentary, schematic, perspective view depicting a sixth alternate concrete masonry wall unit to those depicted in FIGS. 1 and 9-13.

FIG. 15 is a fragmentary, schematic, perspective view generally analogous to FIGS. 1 and 9-14, depicting a seventh alternate concrete masonry wall unit.

DETAILED DISCLOSURE I. General Features of Concrete Masonry Units

Reference numeral 1, FIG. 1, indicates, schematically, a section of a concrete masonry wall or wall unit according to the present disclosure. Herein, example concrete masonry walls I will be depicted and characterized in general applications corresponding to building foundation frost footings. It will be understood from the following descriptions, that the techniques described can be applied in a variety of alternate concrete or masonry block wall structures.

The concrete masonry wall 1 generally includes or comprises a foundation footing 2 and layers or courses 4 of masonry blocks 5. For the example shown, masonry unit 1 comprises four courses or layers 7, 8, 9, and 10, of blocks 5, although it will be understood that a variety of numbers of layers or courses can be used.

In the example shown, course or layer 7 is a bottom most layer, resting on lower footing 2. Course 10, on the other hand, is an uppermost layer of block 5, with various other block and building units as described below, positioned thereon.

In a typical application, frost footing 2 would comprise a foundation wall, with back fill soil along both of opposite sides 15 and 16; although alternatives are possible.

The various courses 7-10, generally are constructed with two types of joints between blocks 5. A first, referred to herein as the bed joints, are the joints (horizontal) between adjacent courses 7, 8, 9 and 10; hence, bed joint 20 between courses 7 and 8; bed joint 21 between courses 8 and 9; and, bed joint 22 between courses 9 and 10. In the bed joints between courses, for example joints 20, 21, 22, mortar is typically provided to secure the blocks 5 in place and to provide strength and integrity to the resulting wall. Also, utilization of mortar in the bed joints 20, 21, 22, helps the builder of the wall to position adjacent blocks while maintaining an appropriately level, upper surface in each course. Thus, for example, the builder can accommodate variations in specific block size due to manufacturing variations (within tolerance), by the presence of the mortar in bed joints between courses, and still accomplish flat, level, upper surfaces in each course.

The various courses 7-10 also generally include a plurality of head joints therein. Head joints are joints, typically vertically oriented, between adjacent blocks 5 within a given layer or course 7-10. Thus, joint 25 is a vertical or head joint between individual blocks 26, 27.

Conventional masonry walls often have a great many head joints therein, each of which is typically a vertical joint in many instances provided with mortar. By comparison to formation of bed joints, positioning the mortar appropriately in each and every one of the required head joints can be a relatively time consuming task. The present disclosure in part concerns provision of block arrangements that can be used to reduce the number of vertical or head joints that require separate head joint mortar applications by provision of features allowing for selected “mortarless” or “mortar-free” head joints. This will be understood from detail and description provided further below.

Still referring to the general features shown in FIG. 1, the footing 2 typically comprises a poured concrete structure sometimes reinforced, for example, with rebar 29. Courses of block, for example courses 7-10 of block 5, are positioned on the footing 2 and built upwardly (vertically) a number of levels appropriate for the construction project involved. In some instances, the upper course 10 of block 5 will comprise fill top block 70 as discussed below, depending on the construction project involved, and the building ordinances, regulations or laws involved.

Above upper layer of course 10, are typically provided various features of the particular construction project involved. In the example shown in FIG. 1, slab 30 is a concrete or cement slab that is poured-in-place with a portion 30 a bearing on an upper surface 10 u of course 10. Also, partition blocks 19 are also provided on upper surface 10 u of course 10. Partition blocks 19 typically provide bearing for a wood framed wail structure or unit 33 comprising sill plate 34 and wall framing 35.

Still referring to FIG. 1, it is noted that certain blocks 5 p are depicted as partial block, through which a cross-section or cut has been taken for the depiction shown of wall section 1, FIG. 1, for convenient viewing in the figure.

II. Block Arrangements for Forming Concrete Masonry Wall Units

As characterized previously, according to the present disclosure there are provided block arrangements that facilitate construction of masonry walls such as concrete masonry wall 1, with a reduced amount of head joints that require separate mortar application, by comparison to many standard arrangements. Advantageously, as indicated above, the block characterized would typically be used to build a wall having courses with mortar in bed joints, between courses, to advantage.

In FIG. 2, an example block 5 in the form of a stretcher block 5 x, is depicted. It is noted that in addition to stretcher block 5 x, an advantageous corner block is provided herein, as discussed later below. In FIG. 2, block 5 x is shown in a form useable as block 5, FIG. 1.

Referring to FIG. 2, block 5 x generally comprises: first and second opposite side walls, faces or face shells 35, 36; and, first and second opposite bearing surfaces 37, 38. The bearing surfaces 37, 38 typically form the top and bottom of the block 5 x, when the block 5 x is set in a course (for example course 7, 8, 9 or 10, FIG. 1). In addition block 5 x has first and second, opposite, ends 40, 39. The ends 40, 39, generally face toward or away from at least one, and typically two, adjacent blocks to block 5 x, in a course 7, 8, 9 or 10.

Block 5 x will typically be constructed with symmetry such that bearing surfaces 37 and 38 are flat, planar and typically the same; and, such that opposite sides or faces 35 and 36 are flat, planar and typically the same. In some instances, it may be desirable to provide one or more of faces or side walls 35, 36 with a decorative appearance. This is a matter of choice, as will be understood from the following. Although alternatives are possible, as discussed below, stretcher blocks 5 x according to the present disclosure are typically constructed such that opposite ends 39 and 40 differ significantly from one another, as characterized below.

Although alternatives are possible, for typical formation of foundation walls, block 5 x will be constructed such that a height distance between bearing surfaces 37, 38, is 6 to 10 inches (15-25 cm); a width distance between sides 35, 36 is 6 to 10 inches (15-25 cm); and a side wall length, defined as the lengths of faces 35, 36 between ends e1, e2, is 8-30 inches (20-76 cm). A typical example block dimension would be height 8 inches (20.3 cm), width 7.625 inches (19.4 cm); and, length 24 inches (61 cm), although alternatives are possible.

In typical use, block 5 x will be oriented such that one of bearing surfaces 37, 38 is directed downwardly, and the other is directed upwardly.

In a typical block 5 x, bearing surfaces 37, 38 are each flat, planar and extend parallel to one another. In a typical block intended to be featureless and to not have a decorative surface, side walls or faces 35, 36 are each planar, parallel or substantially parallel to one another, and perpendicular to bearing surfaces 37, 38.

Block ends 39, 40 are configured with features of projection/receiver arrangements to provide adjacent ones of blocks 5 x, in a course, with a mortarless head joint interlock or interfit possibility. Thus, what is provided is an interfit with selected avoidance of a need for specifically positioning mortar in a resulting head joint, for example head joint 25, FIG. 1, through separate mortar addition from bed joint application. For the example shown, end 39 comprises a first member of a second projection/receiver arrangement, in particular a projection member 39 x; and, end 40 comprises a first member of a first projection/receiver arrangement, for example a receiver member 40 x. Projection member 39 x is sized to interfit with, for example, an analogously shaped and sized receiver member to receiver member 40 x but on an adjacent stretcher block 5 x (or other block) in a course.

Projection member 39 x is more specifically configured with a central projection 42 and side recesses or side recessed sections 43, 44 on opposite sides of the projection 42; and, receiver 40 x is configured with a central recessed section 45 and opposite side projections or ears 46, 47, on opposite sides of the central recessed section 45. The ears 46, 47 are provided with tips 46 t, 47 t to be received adjacent or abutting recessed sections 43, 44 of an adjacent block; and, the projection 42 is sized to be received within the central recess 40 x of an adjacent block.

Typically and preferably, the recessed sections 43, 44, and the projection member 39 x, extend (continuously) between the opposite bearing surfaces 37, 38. Also, typically the recessed section 45 and ears 46, 47 extend (continuously) between the opposite bearing surfaces 37, 38. Typically and preferably, the ears 46, 47 are provided with outer sidewall or face portions of each, at 47 o, 46 o, that are each continuous in a planar manner with a remainder of the faces 36, 35 respectively.

Still referring to FIG. 2, in continuous extension between upper and lower bearing surfaces 37, 38, block 5 x is optionally provided with a central core (aperture or void) arrangement 50, in the example shown comprising spaced cores, apertures or voids 51, each surrounded by concrete in the form of web 52. The presence of, number of, and size of the various cores 51 is in part a matter of choice, depending on the block 5 x and its purpose; and typically 1-4 cores (apertures or voids) 51 are included in aperture arrangement 50, each surrounded by concrete web of block 5 x. In walls built to code, typically there are specifications provided (for example in accord with ASTM C90), concerning the amount of web, etc. for appropriate structural integrity of concrete block, and resulting walls.

Cores 51 provide for a variety of functions. Typically core arrangement 50 is provided to reduce block weight. In some instances, the core arrangement 50 also facilitates handling the blocks. In certain constructions, reinforcing arrangements or concrete grout can be provided in the core arrangement 50, when the block 5 x is installed in a wall or course. Also, the core arrangement 50 can help provide some insulating effect.

For the example stretcher block 5 x depicted in FIG. 2, the core arrangement 50 comprises a plurality of (in the example 3) cores 51, a total length of which, in core extension parallel to sides or faces 35, 36, adds up to at least 60% the length of sides 35, 36; with a width of each core corresponding to at least 60% of a distance between faces 35, 36. Variations are possible.

Attention is now directed to FIG. 3, in which head joint 25 between adjacent blocks 26 and 27, FIG. 1, is shown. FIG. 3 is schematic, and footing 2 (FIG. 1) below blocks 5 in the section of course 7 depicted, is not shown. At head joint 25, mortar is not needed, to provide for secure section of wall 1, FIG. 1. This is partially due to an interlock or interfit provided at joint 25 comprising a projection/receiver arrangement 53 involving projection or projection member 42, on block 26, projecting into recess or receiver member 45, on block 27. In particular, ears 46, 47 are shown projecting toward, and engaging, recessed sections 44 and 43 respectively. Of course, structural integrity of wall 1, FIG. 1, is also facilitated by mortar in bed joints between courses.

Still referring to FIG. 3, and in particular to head joint 25, it is noted that on block 27, central recessed section 45 includes a central portion 45c extending in a direction between sides 35, 36, that portion extending over a distance corresponding to at least 30%, and typically 40%-60%, of a distance between faces 35, 36, and positioned centrally therebetween. Also it is noted that central portions 46 c, 47 c of ears 46, 47, projecting into recess 40, are generally facing one another and toward or away from faces 35, 36. These central straight sections 46 c, 47 c generally extend over a distance of at least 1 inch (2.5 cm) and typically 1.5-3.5 inches (3.8-8.9 cm) in a direction generally parallel to side walls 35, 36. It is noted that in some instances portions 46 c, 47 c and 45 c may bevel slightly in extension from bearing surface 37 to bearing surface 38. Such a design can facilitate de-molding, during block manufacture, in some instances. Similarly, within cores 51, there may be provided some side bevel in extension between surface 37 and 38, again to facilitate de-molding.

Although alternatives are possible, each of sections 46 c, 47 c generally has a depth of extension at least 1.0 inch (2.5 cm), typically 1.5-3.5 inches (3.8-8.9 cm), in extension toward recessed central portion 45 c; the central straight sections 46 c, 47 c, generally being planar sections within recess 45.

Typically a distance between the straight sections 46 c, 47 c (ears 46, 47) will be referred to as a recess width for recess 45. Tip 42 t of projection 42 generally extends between sections 46 c, 47 c, typically filling at least 80% of the recess width. Tip 42 t may be a planar surface, extending generally perpendicular to sides 36, 35 as shown, but alternatives are possible.

Still referring to FIG. 3, head joint 55 is shown between block 26 and block 56. Head joint 55 is specifically formed between projection member 42 on block 56, and receiver member 40 on block 26, at an end opposite projection member 42 of block 26.

The blocks 5 x are sized such that faces or face shells 35, 36 of the various blocks 5 (i.e., blocks 56, 26 and 27, FIG. 3) will align with one another in a generally parallel and planar fashion, on each side of the resulting wall.

Attention is now directed to FIG. 3A and, in particular, to outside or outwardly directed corner transition sections 60, 61 which are positioned along an exterior of projection 42, and extend at an outwardly directed oblique angle, i.e., an angle non-parallel and non-perpendicular relative to a plane of, and to a plane perpendicular to, side walls 36, 35; the angle being indicated at A. Corner transition sections 60, 61 can be beveled corner sections, generally planar in extension between bearing surfaces 37, 38, and directed away (outwardly) from the block in which they are positioned, (block 26) and toward portions of the block with which they engage, block 27. Angle A is often within a range of 120° to 150°, typically 125° to 145°, usually 130°-140°, and, in the example, is about 135°.

Ears 46, 47 for the example block 27 depicted, each include internal or inside, vertical, end edges or internal corner sections 64, 65 respectively, typically as beveled surfaces, remote from recessed section 45 (and positioned in joint 25 adjacent transition sections 61, 60, respectively) and extending at an analogous oblique angle to angle A, with respect to a surface perpendicular to or parallel to, faces 36, 35. This arrangement provides for support of block 5 x against undesirable levels of lateral movement, i.e., movement in the direction of double headed arrow 69. Sections 64, 65 can be viewed as beveled inside corners directed toward one another, i.e., toward an opposite one of ears 46, 47 respectively, formed generally planar in extension between opposite bearing surfaces 37, 38. For the example shown, the length of transition sections 60, 61, in beveled extension away from surfaces 43 x, 43 y respectively, is typically within the range of 0.5-2 inches (1.2-5 cm), although variations are possible.

In general, the width of projection tip 42 t, versus an internal recess width between ears 46, 47, and the spacing between beveled sections 60, 61 on projection 42, and beveled surfaces 64, 65, 46, 47, is selected to inhibit movement before the blocks 5 x are secured in place by mortar in the bed joints. Typically the amount of spacing, for example between surfaces 61, 64 or surfaces 60, 65, is selected so as not to exceed 1 inch (2.5 cm), typically not to exceed 0.5 inch (1.2 cm) and usually not to exceed 0.125 inch (0.3 cm). A typically spacing is 0.0625 inch (0.16 cm). Some spacing facilitates installation. Preferably when installed, ears 46, 47 abut recessed sections 43 y, 43 x, respectively.

In a typical arrangement, recessed sections 43, 44 include sections 43 x, 43 y which extend generally perpendicular to adjacent side walls 36, 35 respectively. Typically each of the surfaces 43 x, 43 y extends inwardly from an adjacent face (36, 35 respectively), an amount of at least 1 inch (2.5 cm), typically at least 1.2 inches (3 cm), usually within the range of 1.2 to 3 inches (3-7.6 cm).

Referring again to FIG. 1, along an uppermost course 10 of block 5 it may be desirable to use block 5 having an upper bearing surface with less area occupied by core arrangement 50, than in the other, lower, courses 7, 8, 9. For example, this may be required by some building ordinances, regulations or laws, depending upon the jurisdiction. In general, a high amount of upper bearing surface 37 being devoid of void area, facilitates support of any additional structure positioned above the upper course, 10. In FIG. 4, such a block 70, referred to herein as a fill top block, is depicted. In general block 70 is in the outer shape or form of stretcher block 5 x, with respect to opposite faces 35, 36 and bearing surfaces 37, 38; and, ends 39 and 40. Typically block 70 only differs from other stretcher blocks 5 x in lower courses by having less core area (aperture area or void volume) at surface 37.

With respect to this, attention is directed to FIG. 4A, which shows a side elevational view of block 40, directed toward face 35. Engagement between core 73 and surface 37, is indicated. Within core 73 (partially through block 70, from bearing surface 37 to bearing surface 38), is provided an internal shoulder shelf or handle 74. This facilitates handling by the wall builder, in use. Reference numbers 75A, 75B, 75C show core volume. It is noted that cores 75B, 75C, do not extend completely between bearing surfaces 37, 38. Thus, surface 37 has a large flat (planar) concrete area, for support of structure above an uppermost course of block.

Typically, core 50 (i.e., core example 75A), engages surface 37 at a location within 0.5-5 inches (1.3-13 cm), typically at least 3 inches (8 cm) from tip 42 t.

Although not shown in FIG. 1, the typical wall 1 will include corners. The principles described herein, for certain mortarless head joints, can be applied adjacent corner block, at head joints between the corner block and blocks 5 (including either block 5 x or block 70) in a course. An example such corner block is shown in FIG. 5, at reference numeral 80. Referring to FIG. 5, corner block 80 includes: inside face 81, opposite outside face 82, head or end 83, opposite receiver or tail end 84; and, a side or corner member 85 of a projection/receiver arrangement. Block 80 further includes opposite bearing surfaces 86, 87.

Referring to block 80: opposite bearing surfaces 86, 87 are typically planar and parallel to one another; and, opposite faces 81, 82 are typically planar and generally perpendicular to the bearing surfaces 86, 87. Outer dimensions of block 80 are typically analogous to those for the stretcher block 5 x, with respect to length, width and height.

Face 82 is typically planar, featureless, perpendicular to side wall 81 and bearing surfaces 86, 87 and is generally directed as a first outside face, in a resulting wall, with respect to a corner made by corner block 80. End 84 generally comprises a receiver member 84 x, constructed analogous to the receiver or receiver member 40, FIG. 2, and includes central recessed section 87 and opposite ears 88, 89. In a typical arrangement, receiver member 84 x would correspond to the same size and shape, as receiver member 40 x for stretcher blocks 5 x.

The particular corner block 80 shown does not include an end with a head projection analogous to projection 42, FIG. 2. Instead, opposite to end 84, block 80 includes, as outer face 83, a flat, planar, often featureless end surface in typical applications, usually perpendicular or nearly to faces 82 and 81, and to bearing surfaces 86, 87. End surface 83 will generally form a second outside wall of a corner made with block 80.

At 85 a second side receiver member 85 x of a second projection/receiver arrangement is depicted. For the particular example block 80 depicted, side receiver member 85 x is a receiver arrangement 91, having a central recessed section 92 and side sections 93, 94 at opposite sides thereof. The sections 93, 94 are sized and spaced to accommodate a projection 42 on another block 5, to form a mortarless head joint. Preferably outer corners or edges 93 o, 94 o respectively, comprise inside, beveled, corner sections analogous to sections 64, 65, to facilitate engagement.

Receiver member 85 x is typically positioned adjacent to and spaced from end face 83, usually a distance within 1-5 inches (2.5-13 cm) of end face 83.

Still referring to FIG. 5, corner block 80 is provided with a core arrangement 80 v comprising individual cores 80 vi, 80 vii and 80 viii therein, each extending continuously between opposite bearing surfaces 86, 87. The cores of core arrangement 80 v would operate analogously to core arrangement 50 discussed above, with analogous features and characteristics. Due to the shape of member block 80 (with side recess 85), core 80 viii, is smaller than the other two cores 80 vi, 80 viii.

Attention is now directed to FIG. 6, in which a portion of course 7 is depicted, this time showing corners 110, 111. FIG. 6 is schematic, and thus footing 2 is not depicted. In FIG. 6, the viewpoint is directed downwardly upon course 7, and stretcher blocks 5 x can be seen engaging corner blocks 80. More specifically, each corner block 80 is engaged by at least one (in the example two) stretcher block 5 x. The engagement is by a projection member on and end of each of the stretcher blocks 5 x extending into one of the two receiver members on the corner block 80.

Still referring to FIG. 6, it is noted that between corners 110, 111, stretcher blocks 5 x extend toward one another. However, since each of the corner blocks 110, 111 is configured to receive a projection on an adjacent stretcher block 5 x, along side wall 120, eventually at least one joint will occur that does not involve an intact stretcher block 5 x engaged and interfit at both ends with the two wall sections 120 a, 120 b.

One approach to addressing this issue, would be to provide an alternative stretcher block, not shown, having a projection analogous to projection 42 (with side recessed wall sections 43, 44), FIG. 2, at each of two opposite ends. Then, if wall sections 120 b, 120 a were sized such that the space between them exactly equaled such an alternative stretcher block, the block could be fit in place, maintaining mortarless joints. Although possible, typically this will not be practical for at least two reasons: (a) it is unlikely the wall 120 would be constructed with exactly the right spacing between sections 120 a, 120 b; and (b) the approach requires the construction and purchase of a special alternative stretcher block having a projection member of a projection/receiver arrangement on both ends, and thus only used in such a location.

Typically, with foundation structures, the structures are not precisely measured and built to exactly accommodate a specific, whole integer, number of stretcher blocks in a course. Rather at a location along the wall length, at least one of adjacent blocks will be cut, fragmented, or otherwise fit, to form joints within each course. At such a location, one or more partial or cut blocks, with mortar applied in an associated head joint will be used. Thus, the configuration of wall 120 with tails 121, 122 directed toward one another, is constructed in anticipation that along wall 120 such a joint requiring one or more partial blocks and mortar in at least one head joint will be encountered.

From the above, it will be understood that wall units constructed with block 5 x and corner blocks 80 according to the present description, will not be completely mortar free or mortarless with respect to mortar addition at every head joint. Rather, typically each course will include selected head joints between block fragments or portions (or a block and block fragments or portions), that include added head joint mortar. However, among and between intact stretcher blocks and corner blocks 80, mortarless head joints are possible.

Still referring to FIG. 6, it is noted that for the next course 8 above course 7, the individual blocks will be positioned so that the head joints are staggered. This is shown in FIG. 1, for example. In the arrangement of FIG. 6, this can be accommodated by positioning a corner block at corner 110 on the next above course, which is oriented with the side recess 85, FIG. 5, directed down wall 123, and with end 84 directed down wall section 120 a.

Referring to FIG. 1, course 10, using fill top block 70, can be constructed analogously to course 7, FIG. 6; and, a fill top version of corner block 80 can be used.

Thus, the techniques described herein can be used to more rapidly construct foundation walls and similar wall units, due to a substantial reduction in time needed for mortar placement in head joints. It is noted that typically, it is preferred to construct a wall course using block 5 by positioning first a block with a receiver, and then positioning a block with a projection into the receiver. Thus, a convenient construction for corner blocks, is with two receivers as shown in FIG. 5; and, a convenient structure for stretcher blocks, is with one receiver and one opposite projection. Alternatives are possible. For example, corner blocks could be constructed with one receiver and one projection, in either of two possibilities: i.e., a receiver at either the end or the side; and, a projection at either the side or the end. Further, stretcher blocks could be constructed have are either two opposite projections or two opposite receivers. However, these variations are generally not as practical as the arrangements shown in FIGS. 3, 4 and 5 for the reasons that: a minimum number of mold variations are used for the arrangements of FIGS. 3, 4 and 5; and, as indicated above, it is generally convenient to form a head joint by first positioning a block with tail end or receiver member in place in a course, and then bring the projection or head into engagement.

III. Additional Block; Example Wall Arrangements; FIGS. 7-15

Attention is directed to FIG. 9, which schematically depict a section 200 of a wall alternative to that depicted in FIG. 1. Section 200 includes a footing 202 analogous to footing 2, with rebar 29. Further, wall unit 200 includes courses 7, 8, and 9 of stretcher block 5. Of course the courses 7, 8, 9 can be constructed to include corners with corner block 80 used analogous to corners 110, 111, FIG. 6. Also, fill top block 70 can be used in course 9, if desired. Also, an alternative number of courses can be used.

Upper surface 9 u of upper course 9 has a layer of course 230 of double ledge blocks 231 thereon. An example of such a double ledge block 231 is shown in FIG. 8. Referring to FIG. 8, block 231 comprises: upper bearing surface 232, lower bearing surface 233, opposite sides or faces 234, 235 and opposite end faces 236, 237. The faces 234, 235 are typically planar and shaped to bevel or slant inwardly, in extension from upper bearing surface 232 to lower bearing surface 233. This creates a wide upper surface 232, for bearing of building features thereon. Still referring to FIG. 8, block 231 is typically a masonry block including central core arrangement 250, for weight reduction. End walls 236, 237 extend perpendicularly to bearing surfaces 232, 233. In head joints between adjacent blocks 231 in course 230, mortar may be used.

Referring to FIG. 9, as a result of the utilization of double ledge blocks 231, upper surface 230 u is sufficiently wide to include, bearing thereon, facing brick 260, slab 270 and wall unit 280 comprising sill plate 281 and wall framing 282. Facing 260 and slab 270 are positioned on opposite sides of a course 290 of facing block 19.

Attention is now directed to FIG. 10 in which a section 300 of a masonry wall unit is depicted. Section 300 includes footing 302 with rebar 329 extending therethrough. Wall section 300 includes three courses 7, 8 and 9 of blocks 5. These features can generally be the same as are analogous to those previously discussed in connection with FIG. 1 and related figures. Above upper surface 9 u, of wall course 9, is positioned a course 330 of single ledge block 331. Such block 331 is depicted in FIG. 7.

Referring to FIG. 7, single ledge block 331 includes upper bearing surface 332, lower bearing surface 333, sides or side faces 334, 335, and opposite end faces 336 and 337. Faces 334, 336, and 337, generally extend perpendicularly to upper and lower bearing walls 332, 333. However, face 335 is generally a beveled surface, extending at an angle non-orthogonal to surfaces 332, 333, and beveling inwardly in extension from upper surface 332 to lower surface 333. Referring to FIG. 10, course 330 and block 331 provide for an upper bearing surface 330 u, sufficiently wide to support thereon a course of partition block 19, facing 360 of brick and wall structure 280 comprising sill plate 281 and wall framework 282. Slab 370 is not depicted bearing on wall section 300. However, in some embodiments of slab 370 could be poured with a portion bearing on selected features that provide a load bearing downwardly through courses 7, 8, 9 to footing 302.

Of course with the arrangement of FIG. 10, as with the arrangement of FIGS. 1 and 9, the number of courses and detail features within the courses, can be varied from those shown. This is true for the remaining wall sections described, with respect to FIGS. 11-15.

Referring next to FIG. 11, an additional wall section 400 is depicted. Again, footing 402 is provided with rebar 29 therein. Courses 7, 8, 9 of stretcher blocks 5 x are depicted. Of course, corners can be managed in a manner analogous to that discussed above in connection with FIG. 6; and, fill top stretcher block 80 can be used if desired. Above upper level 9 u of course 9 is provided a course 430 of single ledge block 331, FIG. 7. This provides an upper surface 430 u of course 430 sufficiently wide to support opposite slabs 440, 441 and a course of partition block 19. Above partition block 19 is provided a wall structure 450 comprising fill plate 451 and wall framework 452.

Of course in some alternatives, in place of single ledge block 331, a double ledge block 231 can be used, provided a wider upper bearing surface, to bear more structure.

In FIG. 12 a wall section 500 is depicted comprising a footing 502 with rebar 29 therein. Position on footing 502 is courses 7, 8, and 9 of stretcher blocks 5. Of course corners can be managed analogous to corners 110, 111, FIG. 6. Above upper surface 9 u of course 9, is provided a course 120 including: double ledge blocks 231, FIG. 8 and, occasionally (between double ledge blocks 231) support or bearing block 530. Bearing block 530 is sized to extend outwardly from opposite sides of the wall sufficiently, to support, bearing thereon, slabs 540, 541. Thus slabs 540, 541 are supported by spaced bearing blocks 530 positioned in course 520. Above course 520 is provided partition block 519, in this instance a wider block than block 19 previously shown. Above block 519 is supported a wall unit 550 comprising a double wall including a double sill plate 551 and two wall framework sections 552.

Attention is now directed to FIG. 13 in which yet another variation is shown at wall structure 600. Structure 600 includes footing 602 having a rebar 29 therein. Above footing 602 are provided courses 7, 8, and 9 of stretcher block 5. Of course corners could be managed in accord with the discussion for corners 110, 111, FIG. 6. Above upper surface 9 u of course 9 is provided as a course 610 of single ledge block 331, FIG. 7. Above course 610 are positioned several items. For example concrete slab 630 is shown poured in place, extending through an opening in a side wall indicated generally at 631. Also provided is a course of partition block 19 supporting a wall unit 650 comprising sill plate 651 and wall framework 552.

Referring now to FIG. 14, wall unit 700 is depicted comprising a footing 702 with rebar 29 therein. Positioned above footing 702 are courses 7, 8, and 9 of stretcher block 5 x. Corners can be managed analogous to the description above for corners 110, 111 FIG. 6. Above upper surface 9 u, of course 9, is provided a course 720 of double ledge block 231, FIG. 8. Above that is provided a course 721 of wide partition block 730. Slabs 750 and 751 are shown poured in place, in this instance not supported by the wall unit 700. Above course 721 is provided a double wide wall unit 760 comprising a first wall 761 with a sill plate 762 and framework 763, and a second wall 771 comprising a sill plate 772 and wall framework 773. The wall section 700 of FIG. 14 may comprise, for example, a party wall between apartments or other building units. If desired, an arrangement can be provided, for example analogous to FIG. 12, for supporting slabs 751, 752.

Attention is now directed to FIG. 15, in which a further wall section 800 is depicted comprising a footing 802 having rebar 29 therein. Above footing 802 are provided courses 7, 8, 9 of stretcher block 5 x. Corners can be managed generally analogously to those discussed previously with respect to FIG. 6, at 110, 111. Above an upper surface 9 u of course 9 is provided a course 820 of double ledge block 231. Above double ledge block 231 is provided, bearing thereon, slab 840, a course 841 of partition block 19 and facing 842 of brick 843. Above partition block 19 is provided a wall section 870 comprising a sill plate 871 and wall framework 872.

From the above examples it will be apparent that techniques as described herein can be applied in a variety of arrangements and to form a variety of walls.

IV. Example Materials

Blocks of the type described herein for stretcher blocks 5 x (whether or not in the form of fill top blocks 870) and corner blocks 80 can be formed in the manner of concrete blocks; i.e., as wet cast concrete block or dry cast concrete block. The features characterized lend themselves to application as either. Dry cast methods for formation of concrete can be advantageous in some instances.

V. Some General Observations

In accord with one aspect of the present disclosure, a concrete block adapted to be inter fit, without modification, with at least one and typically two additional concrete blocks in a wall course, with mortarless head joints between the concrete block and the at least one additional concrete block is provided. There is no specific requirement that the blocks be applied in a wall course such that there is no mortar in any head joint within the wall. Rather the concrete block is adapted to be interfit with at least one adjacent block, as indicated, without the need of adding head joint mortar in the associated head joint, if desired. As explained above, in some walls, dimensions may not provide for a complete positioning of blocks in a course, with no mortar in any head joint. Typically, the blocks are used with mortar in bed joints.

Typically, the block includes a concrete block body comprising: first and second opposite bearing surfaces; first and second opposite sides or faces; and, first and second opposite ends. The first and second opposite bearing surfaces are usually oriented planar and as mirror images of one another, as top and bottom surfaces of the block when positioned in a wall course. The first and second opposite faces, generally provide portions of opposite sides of a wall formed with the block, and typically the side faces are planar and without decorative feature, although variations are possible. The first and second opposite ends generally face toward and away from at least one adjacent block in the course. When the block is a stretcher block, typically the opposite ends face toward and away from the two adjacent blocks. When the block is a corner block, typically one of the ends is positioned facing an adjacent block and the opposite second end forms an outside corner directed away from that block which is adjacent the first end.

With block according to the present disclosure, the first end comprises a first member of a first projection/receiver arrangement. Typically the first member of the first projection/receiver arrangement is a receiver member, although alternatives are possible. The typical receiver member comprises a unshaped channel formed in continuous extension between the opposite bearing surfaces, and including a central recessed section and first and second opposite sides or ears. The central section (which is recessed) along with the opposite ears define a u-shaped recess in the first end of the blocked body. The u-shaped recess is configured as a receiver (or tail) member to receive a projection on an adjacent block, with a mortarless head joint formed at the resulting junction, in use.

In an example shown, the first side or ear includes an inside corner transition portion or beveled surface remote from the central recessed section, which is directed toward the u-shaped recess and toward the second ear and which extends non-parallel and non-perpendicular to the first face; and, the second side ear includes an inside corner transition portion or beveled surface remote from the central recessed section, oriented as a mirror image of the first side projection and thus directed toward the u-shaped recess and extending non-parallel and non-perpendicular to the first (and thus the second) side or face.

The concrete blocks also include further a first member of a second projection/receiver arrangement. The first member of the second projection/receiver arrangement generally comprises one of: a first projection member or projection; and, a second receiver or receiver member.

When the first member of the second projection/receiver arrangement comprises a first projection or projection member, it is typically positioned at the block second end, projecting in a direction opposite the first member of the first projection/receiver arrangement. In such circumstances, the first projection member would typically comprise a center projection having first and second opposite side recessed sections on opposite sides thereof. The projection member would extend between the first and second opposite bearing surfaces, and project from an end of the block body in a direction away from the first end. Typically the first projection member has first and second opposite outside corner transition sections, portions or beveled surfaces adjacent the first and second opposite side recessed sections. The transition portions typically and preferably extend non-parallel and non-perpendicular to first and second opposite side recessed wall sections of the first projection member. The first projection member also typically has a projection tip, usually with the width corresponding to at least 80% of the recess width of the first recess member.

In circumstances in which the concrete block body includes the first end comprising a first member of a first projection/receiver arrangement as characterized, and a second end comprising a first projection of a second projection receiver arrangement is characterized, the block is a stretcher block, configured for engagement with other, analogous, stretcher blocks or with corner blocks in a wall course.

As indicated above, in some instances the first member of a second projection/receiver comprises a second receiver member. When such is the case, and the block is a corner block, the receiver member is positioned on a side of the block adjacent to, but spaced from the second end of the block, typically within a distance of about 1-5 inches (2.5-13 cm) of the second end of the block. The second receiver member may be otherwise configured analogously to the first receiver member, except directed to a side of the block as opposed to an end.

Alternative examples are identified, in which the corner block either includes: two projection members; one on an end, one on a side; or, one receiver member and one projection member (the first being oriented at the end or the side, with the second either at the side or the end respectively). Also, the stretcher block can comprise either of two receiver members, or two projection members. These arrangements, which can be constructed with features as characterized herein above, are usable, but typically not preferred. 

1. A concrete block adapted to be interfit, without modification, with at least one additional concrete block in a wall course, with a mortarless head joint between the concrete block and the at least one additional concrete block; the concrete block comprising: (a) a concrete block body including: first and second, opposite, bearing surfaces; first and second, opposite faces; and, first and second, opposite, block ends; (i) the first block end comprising a first member of a first projection/receiver arrangement; (A) the first member of the first projection/receiver arrangement comprising a first receiver member; (1) the first receiver member comprising a central recessed section positioned between first and second, opposite, ears; the central recessed section and first and second ears defining a u-shaped recess at the first end of the block body; (2) the u-shaped recess extending continuously between the first and second, opposite, bearing surfaces; (3) the first ear including an inwardly directed first corner transition portion remote from the central recessed section; the first corner transition portion: being directed toward the second ear; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (4) the second ear including an inwardly directed second corner transition portion remote from the central recessed section; the second corner transition portion: being directed toward the first ear; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (b) the concrete block body further including a first member of a second projection/receiver comprising one of: a first projection member, and, a second receiver member; (i) the first projection member, when present, being at the block second end and comprising a central projection positioned between first and second opposite side recessed sections; (A) the first projection member extending continuously between the first and second, opposite, bearing surfaces and projecting from a remainder of the block body in a direction away from the first end; and, (B) the first projection member having first and second, opposite, outside corner transition portions adjacent the first and second, opposite, side recessed sections respectively; (1) the first outside corner transition portion being outwardly directed and extending non-parallel and non-perpendicular to the first face; and (2) the second outside corner transition portion being outwardly directed and extending non-perpendicular and non-parallel to the second face; and, (ii) the second receiver member, when present, being in the block second face and adjacent to, and spaced from, the block second side sections; (A) the second receiver member comprising a central recessed section and opposite first and second side sections; (1) the second receiver member extending continuously between the first and second bearing surfaces and including a first inside corner section on the first side section at a location remote from the central recessed section and directed toward the second side section; the first inside corner section extending non-perpendicular and non-parallel to the block second face; and (2) the second side section including a second inside corner section on the second side section at a location remote from the central recessed section, directed toward the first side section and extending non-perpendicular and, non-parallel to the block second face; and, (3) the central recessed section and opposite first and second side sections of the second receiver member defining a u-shaped side recess extending continuously between the first and second, opposite, bearing surfaces.
 2. A concrete block according to claim 1 wherein: (a) the first member of the second projection/receiver arrangement is the second receiver member of 1(b)(ii) positioned in the second face at a location adjacent the block second end; and, (b) the concrete block is configured as a corner block with a flat surface at the second end.
 3. A concrete block according to claim 2 wherein: (a) the u-shaped side recess of the second receiver member is spaced a distance of at least 2.5 cm and not more than 13 cm from the block second end.
 4. A concrete block according to claim 3 wherein: (a) the first side section of the second receiver member includes a first straight, non-beveled, section at least 2.5 cm deep in extension toward the central recessed section; and, (b) the second side section of the second receiver member includes a first straight, non-beveled, section at least 2.5 cm deep in extension toward the central recessed wall.
 5. A concrete block according to claim 1 wherein: (a) a distance between the opposite first and second bearing surfaces is within the range of 15 cm to 25 cm, inclusive; (b) a distance between the opposite block faces is within the distance of 15 cm to 25 cm, inclusive; and, (c) a total length of the block first side is within the range of 20 cm to 76 cm, inclusive.
 6. A concrete block according to claim 1 wherein: (a) the first member of the second projection/receiver arrangement is the first projection member of 1(b)(i); and, (b) the concrete block is configured as a stretcher block.
 7. A concrete block according to claim 6 wherein: (a) the u-shaped recess of the first receiver member has a first recess width; and, (b) the first projection member has a projection tip with a width corresponding to at least 80% of the first recess width.
 8. A concrete block according to claim 6 wherein: (a) the first and second side recessed sections each include a central section extending parallel to one another and each extending perpendicular to the first and second block sides.
 9. A concrete block according to claim 7 including: (a) a core arrangement surrounded by concrete web and extending continuously between the first and second bearing surfaces.
 10. A concrete block according to claim 9 wherein: (a) the core arrangement comprises a single core surrounded by concrete block and positioned within a distance of 8 cm of the block second end.
 11. A concrete block according to claim 10 wherein: (a) the core arrangement comprises a plurality of cores, each surrounded by concrete block, and having a total core length, in a direction parallel to the first and second sides, of at least 60% of a length of each of the first and second sides.
 12. A wall section including: (a) a block course including first and second stretcher blocks each according to claim 6 positioned adjacent one another with a mortarless head joint therebetween; (i) the first projection member at the second end of the second stretcher block projecting into the first receiver member at the first end of the first block.
 13. A wall section including: (a) a block course including first and second concrete blocks; (i) the first concrete block comprising a corner block according to claim 2; (ii) the second concrete block comprising a stretcher block according to claim 6; (iii) the second concrete block being positioned with the first projection member thereon projecting into one of the first and second receiver members of the first concrete block; and (iv) a head joint between the first and second concrete blocks being mortarless.
 14. A concrete block adapted to be interfit, without modification, with at least one additional concrete block in a wall course, with a mortarless head joint between the concrete block and the at least one additional concrete block; the concrete block comprising: (a) a concrete stretcher block body including: first and second, opposite, bearing surfaces; first and second, opposite, faces; and, first and second, opposite, block ends; (i) the first block end comprising a first member of a first projection/receiver arrangement including one of: (A) a first receiver member comprising: (1) a central recessed section positioned between first and second, opposite, ears; the central recessed section and first and second ears defining a u-shaped recess at the first end of the block body; (2) the u-shaped recess extending continuously between the first and second, opposite, bearing surfaces; (3) the first ear including an inwardly directed first corner transition portion remote from the central recessed section; the first corner transition portion: being directed toward the second ear; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (4) the second ear including an inwardly directed second corner transition portion remote from the central recessed section; the second corner transition portion: being directed toward the first ear; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (B) a first projection member comprising a central projection positioned between first and second opposite side recessed sections; (1) the first projection member extending continuously between the first and second, opposite, bearing surfaces and projecting from a remainder of the block body in a direction away from the first end; and, (2) the first projection member having first and second, opposite, outside corner transition portions adjacent the first and second, opposite, side recessed sections respectively;  (I) the first outside corner transition portion being outwardly directed and extending non-parallel and non-perpendicular to the first face; and  (II) the second outside corner transition portion being outwardly directed and extending non-perpendicular and non-parallel to the second face; and, (ii) the block second end comprising a first member of a second projection/receiver arrangement comprising one of: (A) a first receiver member comprising: (1) a central recessed section positioned between first and second, opposite, ears; the central recessed section and first and second ears defining a u-shaped recess at the second end of the block body; (2) the u-shaped recess at the second end of the block body extending continuously between the first and second, opposite, bearing surfaces; (3) the first ear at the second end including an inwardly directed first corner transition portion remote from the central recessed section; the first corner transition portion: being directed toward the second ear at the second end; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (4) the second ear at the second end including an inwardly directed second corner transition portion remote from the central recessed section; the second corner transition portion: being directed toward the first ear at the second end; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (B) a first projection member comprising a central projection positioned between first and second opposite side recessed sections; (1) the first projection member extending continuously between the first and second, opposite, bearing surfaces and projecting from a remainder of the block body in a direction away from the first end; and, (2) the first projection member having first and second, opposite, outside corner transition portions adjacent the first and second, opposite, side recessed sections respectively;  (I) the first outside corner transition portion being outwardly directed and extending non-parallel and non-perpendicular to the first face; and  (II) the second outside corner transition portion being outwardly directed and extending non-perpendicular and non-parallel to the second face.
 15. A concrete block adapted to be interfit, without modification, with at least one additional concrete block in a wall course, with a mortarless head joint between the concrete block and the at least one additional concrete block; the concrete block comprising: (a) a concrete corner block body including: first and second, opposite, bearing surfaces; first and second, opposite, faces; and, first and second, opposite, block ends; (i) the first block end comprising a first member of a first projection/receiver arrangement comprising one of: (A) a first receiver member comprising: (1) a central recessed section positioned between first and second, opposite, ears; the central recessed section and first and second ears defining a u-shaped recess at the first end of the block body; (2) the u-shaped recess extending continuously between the first and second, opposite, bearing surfaces; (3) the first ear including an inwardly directed first corner transition portion remote from the central recessed section; the first corner transition portion: being directed toward the second ear; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (4) the second ear including an inwardly directed second corner transition portion remote from the central recessed section; the second corner transition portion: being directed toward the first ear; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (B) a first projection member comprising a central projection positioned between first and second opposite side recessed sections; (1) the first projection member extending continuously between the first and second, opposite, bearing surfaces and projecting from a remainder of the block body in a direction away from the second end; and, (2) the first projection member having first and second, opposite, outside corner transition portions adjacent the first and second, opposite, side recessed sections respectively;  (I) the first outside corner transition portion being outwardly directed and extending non-parallel and non-perpendicular to the first face; and  (II) the second outside corner transition portion being outwardly directed and extending non-perpendicular and non-parallel to the second face; and, (ii) the second block end comprising a flat end surface and including a first member of a second projection/receiver arrangement adjacent to and spaced from the end surface comprising one of: (A) a second receiver member comprising a central recessed section positioned between first and second, opposite, side sections; the central recessed section and first and second ears defining a u-shaped recess in the second side and spaced from the flat end surface of the block body; (1) the u-shaped recess extending continuously between the first and second, opposite, bearing surfaces; (2) the first side section including an inwardly directed first corner transition portion remote from the central recessed section; the first corner transition portion: being directed toward the second side section; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (3) the second side section including an inwardly directed second corner transition portion remote from the central recessed section; the second corner transition portion: being directed toward the first side section; extending non-parallel and non-perpendicular to the first face; and, extending continuously between the first and second, opposite, bearing surfaces; and, (B) a second projection member comprising a central projection positioned between first and second opposite side recessed sections; (1) the second projection member extending continuously between the first and second, opposite, bearing surfaces and projecting from a remainder of the block body in a direction away from the first face; and, (2) the second projection member having first and second, opposite, outside corner transition portions adjacent the first and second, opposite, side recessed sections respectively;  (I) the first outside corner transition portion being outwardly directed and extending non-parallel and non-perpendicular to the second face; and  (II) the second outside corner transition portion being outwardly directed and extending non-perpendicular and non-parallel to the second face. 